Re: [PATCHv8 0/8] System Cache support for GPU and required SMMU support

[Will Deacon <will@kernel.org>]

On Tue, Nov 17, 2020 at 08:00:39PM +0530, Sai Prakash Ranjan wrote:
> Some hardware variants contain a system cache or the last level
> cache(llc). This cache is typically a large block which is shared
> by multiple clients on the SOC. GPU uses the system cache to cache
> both the GPU data buffers(like textures) as well the SMMU pagetables.
> This helps with improved render performance as well as lower power
> consumption by reducing the bus traffic to the system memory.
> 
> The system cache architecture allows the cache to be split into slices
> which then be used by multiple SOC clients. This patch series is an
> effort to enable and use two of those slices preallocated for the GPU,
> one for the GPU data buffers and another for the GPU SMMU hardware
> pagetables.
> 
> Patch 1 - Patch 6 adds system cache support in SMMU and GPU driver.
> Patch 7 and 8 are minor cleanups for arm-smmu impl.
> 
> Changes in v8:
>  * Introduce a generic domain attribute for pagetable config (Will)
>  * Rename quirk to more generic IO_PGTABLE_QUIRK_ARM_OUTER_WBWA (Will)
>  * Move non-strict mode to use new struct domain_attr_io_pgtbl_config (Will)

Modulo some minor comments I've made, this looks good to me. What is the
plan for merging it? I can take the IOMMU parts, but patches 4-6 touch the
MSM GPU driver and I'd like to avoid conflicts with that.

Will